Examples

Consuelo and Sunny officially divorced in 1921, and after obtaining an annulment from the Pope (as Sunny had converted to Catholicism and the Balsan family viewed the marriage between Consuelo and Jacques as unsanctioned due to her divorce), Gladys finally became the (2nd) 9th Duchess of Marlborough at age 40.

I suspect that Hanover could get an annulment if she pressed for one — Giulianni was cheating on her and one of the reasons that an annulment is often granted is if one of the parties had “no intention of fidelity” when they got married in the first place.